In the recent years, attention has been paid to the technology of storing heat energy, i.e. heat storage technology, as one of the technologies to solve the recent energy problems. Heat storage technology is a technology to effectively utilize natural energy such as solar heat and geothermal heat, and residual heat from air-conditioners; for example, in houses, heat storage technology is used as a technology involving storing heat by use of inexpensive nighttime electric power, and using the stored heat as a multi-purpose heat source, thereby reducing mid-day power consumption.
For example, Patent Document 1 discloses a heat storage material composed mainly of a polyhydric aliphatic alcohol having an isomeric arrangement such as that having symmetric arrangement with respect to the center of the chain, and employing mannitol and/or the like as the polyhydric aliphatic alcohol.
Further, Patent Document 2 discloses a heat storage material composed mainly of a sugar alcohol selected from the group consisting of erythritol, mannitol and galactitol, and utilizing the latent heat of fusion of such compounds.
Further, Patent Document 3 discloses a composition comprising a heat storage material that is prepared by the blend of a urea compound into an organic compound being solid at normal temperature and having a solid phase transition point and that employs trimethylolmethane, pentaerythritol or the like as that organic compound, and use of the composition comprising the heat storage material for heat supply utilizing latent heat of fusion.
[Patent Document 1] JP-A-63-500946
[Patent Document 2] JP-A-5-32963
[Patent Document 3] JP-A-2001-152141